slirp/socket.c

   1 /*
   2  * Copyright (c) 1995 Danny Gasparovski.
   3  *
   4  * Please read the file COPYRIGHT for the
   5  * terms and conditions of the copyright.
   6  */
   7
   8 #include "qemu-common.h"
   9 #include <slirp.h>
  10 #include "ip_icmp.h"
  11 #ifdef __sun__
  12 #include <sys/filio.h>
  13 #endif
  14
  15 static void sofcantrcvmore(struct socket *so);
  16 static void sofcantsendmore(struct socket *so);
  17
  18 struct socket *solookup(struct socket **last, struct socket *head,
  19         struct sockaddr_storage *lhost, struct sockaddr_storage *fhost)
  20 {
  21     struct socket *so = *last;
  22
  23     /* Optimisation */
  24     if (so != head && sockaddr_equal(&(so->lhost.ss), lhost)
  25             && (!fhost || sockaddr_equal(&so->fhost.ss, fhost))) {
  26         return so;
  27     }
  28
  29     for (so = head->so_next; so != head; so = so->so_next) {
  30         if (sockaddr_equal(&(so->lhost.ss), lhost)
  31                 && (!fhost || sockaddr_equal(&so->fhost.ss, fhost))) {
  32             *last = so;
  33             return so;
  34         }
  35     }
  36
  37     return (struct socket *)NULL;
  38 }
  39
  40 /*
  41  * Create a new socket, initialise the fields
  42  * It is the responsibility of the caller to
  43  * insque() it into the correct linked-list
  44  */
  45 struct socket *
  46 socreate(Slirp *slirp)
  47 {
  48   struct socket *so;
  49
  50   so = (struct socket *)malloc(sizeof(struct socket));
  51   if(so) {
  52     memset(so, 0, sizeof(struct socket));
  53     so->so_state = SS_NOFDREF;
  54     so->s = -1;
  55     so->slirp = slirp;
  56     so->pollfds_idx = -1;
  57   }
  58   return(so);
  59 }
  60
  61 /*
  62  * remque and free a socket, clobber cache
  63  */
  64 void
  65 sofree(struct socket *so)
  66 {
  67   Slirp *slirp = so->slirp;
  68
  69   if (so->so_emu==EMU_RSH && so->extra) {
  70         sofree(so->extra);
  71         so->extra=NULL;
  72   }
  73   if (so == slirp->tcp_last_so) {
  74       slirp->tcp_last_so = &slirp->tcb;
  75   } else if (so == slirp->udp_last_so) {
  76       slirp->udp_last_so = &slirp->udb;
  77   } else if (so == slirp->icmp_last_so) {
  78       slirp->icmp_last_so = &slirp->icmp;
  79   }
  80   m_free(so->so_m);
  81
  82   if(so->so_next && so->so_prev)
  83     remque(so);  /* crashes if so is not in a queue */
  84
  85   free(so);
  86 }
  87
  88 size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)
  89 {
  90         int n, lss, total;
  91         struct sbuf *sb = &so->so_snd;
  92         int len = sb->sb_datalen - sb->sb_cc;
  93         int mss = so->so_tcpcb->t_maxseg;
  94
  95         DEBUG_CALL("sopreprbuf");
  96         DEBUG_ARG("so = %p", so);
  97
  98         if (len <= 0)
  99                 return 0;
 100
 101         iov[0].iov_base = sb->sb_wptr;
 102         iov[1].iov_base = NULL;
 103         iov[1].iov_len = 0;
 104         if (sb->sb_wptr < sb->sb_rptr) {
 105                 iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
 106                 /* Should never succeed, but... */
 107                 if (iov[0].iov_len > len)
 108                    iov[0].iov_len = len;
 109                 if (iov[0].iov_len > mss)
 110                    iov[0].iov_len -= iov[0].iov_len%mss;
 111                 n = 1;
 112         } else {
 113                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
 114                 /* Should never succeed, but... */
 115                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 116                 len -= iov[0].iov_len;
 117                 if (len) {
 118                         iov[1].iov_base = sb->sb_data;
 119                         iov[1].iov_len = sb->sb_rptr - sb->sb_data;
 120                         if(iov[1].iov_len > len)
 121                            iov[1].iov_len = len;
 122                         total = iov[0].iov_len + iov[1].iov_len;
 123                         if (total > mss) {
 124                                 lss = total%mss;
 125                                 if (iov[1].iov_len > lss) {
 126                                         iov[1].iov_len -= lss;
 127                                         n = 2;
 128                                 } else {
 129                                         lss -= iov[1].iov_len;
 130                                         iov[0].iov_len -= lss;
 131                                         n = 1;
 132                                 }
 133                         } else
 134                                 n = 2;
 135                 } else {
 136                         if (iov[0].iov_len > mss)
 137                            iov[0].iov_len -= iov[0].iov_len%mss;
 138                         n = 1;
 139                 }
 140         }
 141         if (np)
 142                 *np = n;
 143
 144         return iov[0].iov_len + (n - 1) * iov[1].iov_len;
 145 }
 146
 147 /*
 148  * Read from so's socket into sb_snd, updating all relevant sbuf fields
 149  * NOTE: This will only be called if it is select()ed for reading, so
 150  * a read() of 0 (or less) means it's disconnected
 151  */
 152 int
 153 soread(struct socket *so)
 154 {
 155         int n, nn;
 156         struct sbuf *sb = &so->so_snd;
 157         struct iovec iov[2];
 158
 159         DEBUG_CALL("soread");
 160         DEBUG_ARG("so = %p", so);
 161
 162         /*
 163          * No need to check if there's enough room to read.
 164          * soread wouldn't have been called if there weren't
 165          */
 166         sopreprbuf(so, iov, &n);
 167
 168 #ifdef HAVE_READV
 169         nn = readv(so->s, (struct iovec *)iov, n);
 170         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 171 #else
 172         nn = qemu_recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
 173 #endif
 174         if (nn <= 0) {
 175                 if (nn < 0 && (errno == EINTR || errno == EAGAIN))
 176                         return 0;
 177                 else {
 178                         DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
 179                         sofcantrcvmore(so);
 180                         tcp_sockclosed(sototcpcb(so));
 181                         return -1;
 182                 }
 183         }
 184
 185 #ifndef HAVE_READV
 186         /*
 187          * If there was no error, try and read the second time round
 188          * We read again if n = 2 (ie, there's another part of the buffer)
 189          * and we read as much as we could in the first read
 190          * We don't test for <= 0 this time, because there legitimately
 191          * might not be any more data (since the socket is non-blocking),
 192          * a close will be detected on next iteration.
 193          * A return of -1 wont (shouldn't) happen, since it didn't happen above
 194          */
 195         if (n == 2 && nn == iov[0].iov_len) {
 196             int ret;
 197             ret = qemu_recv(so->s, iov[1].iov_base, iov[1].iov_len,0);
 198             if (ret > 0)
 199                 nn += ret;
 200         }
 201
 202         DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
 203 #endif
 204
 205         /* Update fields */
 206         sb->sb_cc += nn;
 207         sb->sb_wptr += nn;
 208         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 209                 sb->sb_wptr -= sb->sb_datalen;
 210         return nn;
 211 }
 212
 213 int soreadbuf(struct socket *so, const char *buf, int size)
 214 {
 215     int n, nn, copy = size;
 216         struct sbuf *sb = &so->so_snd;
 217         struct iovec iov[2];
 218
 219         DEBUG_CALL("soreadbuf");
 220         DEBUG_ARG("so = %p", so);
 221
 222         /*
 223          * No need to check if there's enough room to read.
 224          * soread wouldn't have been called if there weren't
 225          */
 226         if (sopreprbuf(so, iov, &n) < size)
 227         goto err;
 228
 229     nn = MIN(iov[0].iov_len, copy);
 230     memcpy(iov[0].iov_base, buf, nn);
 231
 232     copy -= nn;
 233     buf += nn;
 234
 235     if (copy == 0)
 236         goto done;
 237
 238     memcpy(iov[1].iov_base, buf, copy);
 239
 240 done:
 241     /* Update fields */
 242         sb->sb_cc += size;
 243         sb->sb_wptr += size;
 244         if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
 245                 sb->sb_wptr -= sb->sb_datalen;
 246     return size;
 247 err:
 248
 249     sofcantrcvmore(so);
 250     tcp_sockclosed(sototcpcb(so));
 251     fprintf(stderr, "soreadbuf buffer to small");
 252     return -1;
 253 }
 254
 255 /*
 256  * Get urgent data
 257  *
 258  * When the socket is created, we set it SO_OOBINLINE,
 259  * so when OOB data arrives, we soread() it and everything
 260  * in the send buffer is sent as urgent data
 261  */
 262 void
 263 sorecvoob(struct socket *so)
 264 {
 265         struct tcpcb *tp = sototcpcb(so);
 266
 267         DEBUG_CALL("sorecvoob");
 268         DEBUG_ARG("so = %p", so);
 269
 270         /*
 271          * We take a guess at how much urgent data has arrived.
 272          * In most situations, when urgent data arrives, the next
 273          * read() should get all the urgent data.  This guess will
 274          * be wrong however if more data arrives just after the
 275          * urgent data, or the read() doesn't return all the
 276          * urgent data.
 277          */
 278         soread(so);
 279         tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 280         tp->t_force = 1;
 281         tcp_output(tp);
 282         tp->t_force = 0;
 283 }
 284
 285 /*
 286  * Send urgent data
 287  * There's a lot duplicated code here, but...
 288  */
 289 int
 290 sosendoob(struct socket *so)
 291 {
 292         struct sbuf *sb = &so->so_rcv;
 293         char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
 294
 295         int n, len;
 296
 297         DEBUG_CALL("sosendoob");
 298         DEBUG_ARG("so = %p", so);
 299         DEBUG_ARG("sb->sb_cc = %d", sb->sb_cc);
 300
 301         if (so->so_urgc > 2048)
 302            so->so_urgc = 2048; /* XXXX */
 303
 304         if (sb->sb_rptr < sb->sb_wptr) {
 305                 /* We can send it directly */
 306                 n = slirp_send(so, sb->sb_rptr, so->so_urgc, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 307                 so->so_urgc -= n;
 308
 309                 DEBUG_MISC((dfd, " --- sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 310         } else {
 311                 /*
 312                  * Since there's no sendv or sendtov like writev,
 313                  * we must copy all data to a linear buffer then
 314                  * send it all
 315                  */
 316                 len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 317                 if (len > so->so_urgc) len = so->so_urgc;
 318                 memcpy(buff, sb->sb_rptr, len);
 319                 so->so_urgc -= len;
 320                 if (so->so_urgc) {
 321                         n = sb->sb_wptr - sb->sb_data;
 322                         if (n > so->so_urgc) n = so->so_urgc;
 323                         memcpy((buff + len), sb->sb_data, n);
 324                         so->so_urgc -= n;
 325                         len += n;
 326                 }
 327                 n = slirp_send(so, buff, len, (MSG_OOB)); /* |MSG_DONTWAIT)); */
 328 #ifdef DEBUG
 329                 if (n != len)
 330                    DEBUG_ERROR((dfd, "Didn't send all data urgently XXXXX\n"));
 331 #endif
 332                 DEBUG_MISC((dfd, " ---2 sent %d bytes urgent data, %d urgent bytes left\n", n, so->so_urgc));
 333         }
 334
 335         sb->sb_cc -= n;
 336         sb->sb_rptr += n;
 337         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 338                 sb->sb_rptr -= sb->sb_datalen;
 339
 340         return n;
 341 }
 342
 343 /*
 344  * Write data from so_rcv to so's socket,
 345  * updating all sbuf field as necessary
 346  */
 347 int
 348 sowrite(struct socket *so)
 349 {
 350         int  n,nn;
 351         struct sbuf *sb = &so->so_rcv;
 352         int len = sb->sb_cc;
 353         struct iovec iov[2];
 354
 355         DEBUG_CALL("sowrite");
 356         DEBUG_ARG("so = %p", so);
 357
 358         if (so->so_urgc) {
 359                 sosendoob(so);
 360                 if (sb->sb_cc == 0)
 361                         return 0;
 362         }
 363
 364         /*
 365          * No need to check if there's something to write,
 366          * sowrite wouldn't have been called otherwise
 367          */
 368
 369         iov[0].iov_base = sb->sb_rptr;
 370         iov[1].iov_base = NULL;
 371         iov[1].iov_len = 0;
 372         if (sb->sb_rptr < sb->sb_wptr) {
 373                 iov[0].iov_len = sb->sb_wptr - sb->sb_rptr;
 374                 /* Should never succeed, but... */
 375                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 376                 n = 1;
 377         } else {
 378                 iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_rptr;
 379                 if (iov[0].iov_len > len) iov[0].iov_len = len;
 380                 len -= iov[0].iov_len;
 381                 if (len) {
 382                         iov[1].iov_base = sb->sb_data;
 383                         iov[1].iov_len = sb->sb_wptr - sb->sb_data;
 384                         if (iov[1].iov_len > len) iov[1].iov_len = len;
 385                         n = 2;
 386                 } else
 387                         n = 1;
 388         }
 389         /* Check if there's urgent data to send, and if so, send it */
 390
 391 #ifdef HAVE_READV
 392         nn = writev(so->s, (const struct iovec *)iov, n);
 393
 394         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 395 #else
 396         nn = slirp_send(so, iov[0].iov_base, iov[0].iov_len,0);
 397 #endif
 398         /* This should never happen, but people tell me it does *shrug* */
 399         if (nn < 0 && (errno == EAGAIN || errno == EINTR))
 400                 return 0;
 401
 402         if (nn <= 0) {
 403                 DEBUG_MISC((dfd, " --- sowrite disconnected, so->so_state = %x, errno = %d\n",
 404                         so->so_state, errno));
 405                 sofcantsendmore(so);
 406                 tcp_sockclosed(sototcpcb(so));
 407                 return -1;
 408         }
 409
 410 #ifndef HAVE_READV
 411         if (n == 2 && nn == iov[0].iov_len) {
 412             int ret;
 413             ret = slirp_send(so, iov[1].iov_base, iov[1].iov_len,0);
 414             if (ret > 0)
 415                 nn += ret;
 416         }
 417         DEBUG_MISC((dfd, "  ... wrote nn = %d bytes\n", nn));
 418 #endif
 419
 420         /* Update sbuf */
 421         sb->sb_cc -= nn;
 422         sb->sb_rptr += nn;
 423         if (sb->sb_rptr >= (sb->sb_data + sb->sb_datalen))
 424                 sb->sb_rptr -= sb->sb_datalen;
 425
 426         /*
 427          * If in DRAIN mode, and there's no more data, set
 428          * it CANTSENDMORE
 429          */
 430         if ((so->so_state & SS_FWDRAIN) && sb->sb_cc == 0)
 431                 sofcantsendmore(so);
 432
 433         return nn;
 434 }
 435
 436 /*
 437  * recvfrom() a UDP socket
 438  */
 439 void
 440 sorecvfrom(struct socket *so)
 441 {
 442         struct sockaddr_storage addr;
 443         struct sockaddr_storage saddr, daddr;
 444         socklen_t addrlen = sizeof(struct sockaddr_storage);
 445
 446         DEBUG_CALL("sorecvfrom");
 447         DEBUG_ARG("so = %p", so);
 448
 449         if (so->so_type == IPPROTO_ICMP) {   /* This is a "ping" reply */
 450           char buff[256];
 451           int len;
 452
 453           len = recvfrom(so->s, buff, 256, 0,
 454                          (struct sockaddr *)&addr, &addrlen);
 455           /* XXX Check if reply is "correct"? */
 456
 457           if(len == -1 || len == 0) {
 458             u_char code=ICMP_UNREACH_PORT;
 459
 460             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 461             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 462
 463             DEBUG_MISC((dfd," udp icmp rx errno = %d-%s\n",
 464                         errno,strerror(errno)));
 465             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 466           } else {
 467             icmp_reflect(so->so_m);
 468             so->so_m = NULL; /* Don't m_free() it again! */
 469           }
 470           /* No need for this socket anymore, udp_detach it */
 471           udp_detach(so);
 472         } else {                                /* A "normal" UDP packet */
 473           struct mbuf *m;
 474           int len;
 475 #ifdef _WIN32
 476           unsigned long n;
 477 #else
 478           int n;
 479 #endif
 480
 481           m = m_get(so->slirp);
 482           if (!m) {
 483               return;
 484           }
 485           m->m_data += IF_MAXLINKHDR;
 486
 487           /*
 488            * XXX Shouldn't FIONREAD packets destined for port 53,
 489            * but I don't know the max packet size for DNS lookups
 490            */
 491           len = M_FREEROOM(m);
 492           /* if (so->so_fport != htons(53)) { */
 493           ioctlsocket(so->s, FIONREAD, &n);
 494
 495           if (n > len) {
 496             n = (m->m_data - m->m_dat) + m->m_len + n + 1;
 497             m_inc(m, n);
 498             len = M_FREEROOM(m);
 499           }
 500           /* } */
 501
 502           m->m_len = recvfrom(so->s, m->m_data, len, 0,
 503                               (struct sockaddr *)&addr, &addrlen);
 504           DEBUG_MISC((dfd, " did recvfrom %d, errno = %d-%s\n",
 505                       m->m_len, errno,strerror(errno)));
 506           if(m->m_len<0) {
 507             u_char code=ICMP_UNREACH_PORT;
 508
 509             if(errno == EHOSTUNREACH) code=ICMP_UNREACH_HOST;
 510             else if(errno == ENETUNREACH) code=ICMP_UNREACH_NET;
 511
 512             DEBUG_MISC((dfd," rx error, tx icmp ICMP_UNREACH:%i\n", code));
 513             icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 514             m_free(m);
 515           } else {
 516           /*
 517            * Hack: domain name lookup will be used the most for UDP,
 518            * and since they'll only be used once there's no need
 519            * for the 4 minute (or whatever) timeout... So we time them
 520            * out much quicker (10 seconds  for now...)
 521            */
 522             if (so->so_expire) {
 523               if (so->so_fport == htons(53))
 524                 so->so_expire = curtime + SO_EXPIREFAST;
 525               else
 526                 so->so_expire = curtime + SO_EXPIRE;
 527             }
 528
 529             /*
 530              * If this packet was destined for CTL_ADDR,
 531              * make it look like that's where it came from
 532              */
 533             saddr = addr;
 534             sotranslate_in(so, &saddr);
 535             daddr = so->lhost.ss;
 536
 537             switch (so->so_ffamily) {
 538             case AF_INET:
 539                 udp_output(so, m, (struct sockaddr_in *) &saddr,
 540                            (struct sockaddr_in *) &daddr,
 541                            so->so_iptos);
 542                 break;
 543             default:
 544                 break;
 545             }
 546           } /* rx error */
 547         } /* if ping packet */
 548 }
 549
 550 /*
 551  * sendto() a socket
 552  */
 553 int
 554 sosendto(struct socket *so, struct mbuf *m)
 555 {
 556         int ret;
 557         struct sockaddr_storage addr;
 558
 559         DEBUG_CALL("sosendto");
 560         DEBUG_ARG("so = %p", so);
 561         DEBUG_ARG("m = %p", m);
 562
 563         addr = so->fhost.ss;
 564         DEBUG_CALL(" sendto()ing)");
 565         sotranslate_out(so, &addr);
 566
 567         /* Don't care what port we get */
 568         ret = sendto(so->s, m->m_data, m->m_len, 0,
 569                      (struct sockaddr *)&addr, sizeof(addr));
 570         if (ret < 0)
 571                 return -1;
 572
 573         /*
 574          * Kill the socket if there's no reply in 4 minutes,
 575          * but only if it's an expirable socket
 576          */
 577         if (so->so_expire)
 578                 so->so_expire = curtime + SO_EXPIRE;
 579         so->so_state &= SS_PERSISTENT_MASK;
 580         so->so_state |= SS_ISFCONNECTED; /* So that it gets select()ed */
 581         return 0;
 582 }
 583
 584 /*
 585  * Listen for incoming TCP connections
 586  */
 587 struct socket *
 588 tcp_listen(Slirp *slirp, uint32_t haddr, u_int hport, uint32_t laddr,
 589            u_int lport, int flags)
 590 {
 591         struct sockaddr_in addr;
 592         struct socket *so;
 593         int s, opt = 1;
 594         socklen_t addrlen = sizeof(addr);
 595         memset(&addr, 0, addrlen);
 596
 597         DEBUG_CALL("tcp_listen");
 598         DEBUG_ARG("haddr = %x", haddr);
 599         DEBUG_ARG("hport = %d", hport);
 600         DEBUG_ARG("laddr = %x", laddr);
 601         DEBUG_ARG("lport = %d", lport);
 602         DEBUG_ARG("flags = %x", flags);
 603
 604         so = socreate(slirp);
 605         if (!so) {
 606           return NULL;
 607         }
 608
 609         /* Don't tcp_attach... we don't need so_snd nor so_rcv */
 610         if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {
 611                 free(so);
 612                 return NULL;
 613         }
 614         insque(so, &slirp->tcb);
 615
 616         /*
 617          * SS_FACCEPTONCE sockets must time out.
 618          */
 619         if (flags & SS_FACCEPTONCE)
 620            so->so_tcpcb->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT*2;
 621
 622         so->so_state &= SS_PERSISTENT_MASK;
 623         so->so_state |= (SS_FACCEPTCONN | flags);
 624         so->so_lfamily = AF_INET;
 625         so->so_lport = lport; /* Kept in network format */
 626         so->so_laddr.s_addr = laddr; /* Ditto */
 627
 628         addr.sin_family = AF_INET;
 629         addr.sin_addr.s_addr = haddr;
 630         addr.sin_port = hport;
 631
 632         if (((s = qemu_socket(AF_INET,SOCK_STREAM,0)) < 0) ||
 633             (socket_set_fast_reuse(s) < 0) ||
 634             (bind(s,(struct sockaddr *)&addr, sizeof(addr)) < 0) ||
 635             (listen(s,1) < 0)) {
 636                 int tmperrno = errno; /* Don't clobber the real reason we failed */
 637
 638                 close(s);
 639                 sofree(so);
 640                 /* Restore the real errno */
 641 #ifdef _WIN32
 642                 WSASetLastError(tmperrno);
 643 #else
 644                 errno = tmperrno;
 645 #endif
 646                 return NULL;
 647         }
 648         qemu_setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
 649
 650         getsockname(s,(struct sockaddr *)&addr,&addrlen);
 651         so->so_ffamily = AF_INET;
 652         so->so_fport = addr.sin_port;
 653         if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
 654            so->so_faddr = slirp->vhost_addr;
 655         else
 656            so->so_faddr = addr.sin_addr;
 657
 658         so->s = s;
 659         return so;
 660 }
 661
 662 /*
 663  * Various session state calls
 664  * XXX Should be #define's
 665  * The socket state stuff needs work, these often get call 2 or 3
 666  * times each when only 1 was needed
 667  */
 668 void
 669 soisfconnecting(struct socket *so)
 670 {
 671         so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|
 672                           SS_FCANTSENDMORE|SS_FWDRAIN);
 673         so->so_state |= SS_ISFCONNECTING; /* Clobber other states */
 674 }
 675
 676 void
 677 soisfconnected(struct socket *so)
 678 {
 679         so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
 680         so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
 681 }
 682
 683 static void
 684 sofcantrcvmore(struct socket *so)
 685 {
 686         if ((so->so_state & SS_NOFDREF) == 0) {
 687                 shutdown(so->s,0);
 688         }
 689         so->so_state &= ~(SS_ISFCONNECTING);
 690         if (so->so_state & SS_FCANTSENDMORE) {
 691            so->so_state &= SS_PERSISTENT_MASK;
 692            so->so_state |= SS_NOFDREF; /* Don't select it */
 693         } else {
 694            so->so_state |= SS_FCANTRCVMORE;
 695         }
 696 }
 697
 698 static void
 699 sofcantsendmore(struct socket *so)
 700 {
 701         if ((so->so_state & SS_NOFDREF) == 0) {
 702             shutdown(so->s,1);           /* send FIN to fhost */
 703         }
 704         so->so_state &= ~(SS_ISFCONNECTING);
 705         if (so->so_state & SS_FCANTRCVMORE) {
 706            so->so_state &= SS_PERSISTENT_MASK;
 707            so->so_state |= SS_NOFDREF; /* as above */
 708         } else {
 709            so->so_state |= SS_FCANTSENDMORE;
 710         }
 711 }
 712
 713 /*
 714  * Set write drain mode
 715  * Set CANTSENDMORE once all data has been write()n
 716  */
 717 void
 718 sofwdrain(struct socket *so)
 719 {
 720         if (so->so_rcv.sb_cc)
 721                 so->so_state |= SS_FWDRAIN;
 722         else
 723                 sofcantsendmore(so);
 724 }
 725
 726 /*
 727  * Translate addr in host addr when it is a virtual address
 728  */
 729 void sotranslate_out(struct socket *so, struct sockaddr_storage *addr)
 730 {
 731     Slirp *slirp = so->slirp;
 732     struct sockaddr_in *sin = (struct sockaddr_in *)addr;
 733
 734     switch (addr->ss_family) {
 735     case AF_INET:
 736         if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
 737                 slirp->vnetwork_addr.s_addr) {
 738             /* It's an alias */
 739             if (so->so_faddr.s_addr == slirp->vnameserver_addr.s_addr) {
 740                 if (get_dns_addr(&sin->sin_addr) < 0) {
 741                     sin->sin_addr = loopback_addr;
 742                 }
 743             } else {
 744                 sin->sin_addr = loopback_addr;
 745             }
 746         }
 747
 748         DEBUG_MISC((dfd, " addr.sin_port=%d, "
 749             "addr.sin_addr.s_addr=%.16s\n",
 750             ntohs(sin->sin_port), inet_ntoa(sin->sin_addr)));
 751         break;
 752
 753     default:
 754         break;
 755     }
 756 }
 757
 758 void sotranslate_in(struct socket *so, struct sockaddr_storage *addr)
 759 {
 760     Slirp *slirp = so->slirp;
 761     struct sockaddr_in *sin = (struct sockaddr_in *)addr;
 762
 763     switch (addr->ss_family) {
 764     case AF_INET:
 765         if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) ==
 766             slirp->vnetwork_addr.s_addr) {
 767             uint32_t inv_mask = ~slirp->vnetwork_mask.s_addr;
 768
 769             if ((so->so_faddr.s_addr & inv_mask) == inv_mask) {
 770                 sin->sin_addr = slirp->vhost_addr;
 771             } else if (sin->sin_addr.s_addr == loopback_addr.s_addr ||
 772                        so->so_faddr.s_addr != slirp->vhost_addr.s_addr) {
 773                 sin->sin_addr = so->so_faddr;
 774             }
 775         }
 776         break;
 777
 778     default:
 779         break;
 780     }
 781 }
 782
 783 /*
 784  * Translate connections from localhost to the real hostname
 785  */
 786 void sotranslate_accept(struct socket *so)
 787 {
 788     Slirp *slirp = so->slirp;
 789
 790     switch (so->so_ffamily) {
 791     case AF_INET:
 792         if (so->so_faddr.s_addr == INADDR_ANY ||
 793             (so->so_faddr.s_addr & loopback_mask) ==
 794             (loopback_addr.s_addr & loopback_mask)) {
 795            so->so_faddr = slirp->vhost_addr;
 796         }
 797         break;
 798
 799     default:
 800         break;
 801     }
 802 }